1. Field of the Invention
The present invention relates to reflectors to direct and/or project light and sound emission from a source.
2. Background of the Invention
A variety of emission reflectors are known in the art. For example, fluorescent bulbs have reflectors for illumination that are common in the home. Headlamps of automobiles have parabolic and other shaped reflectors for directing light. Elliptical troughs are used to reimage flashlamps to produce high intensity light for treating and removing coatings.
Accordingly there are many patents disclosing trough reflectors, for example, U.S. patent to Hoffschmidt et al. entitled, Trough-type Parabolic Concentrator, and U.S. Pat. No. 6,035,850 to Deidewig, entitled Concentrator of Focusing Solar Radiation.
Many commercial lamp systems use standard reflector troughs to deliver light. For example, to strip paint, a flashlamp is placed at one focus of an elliptical trough and the painted surface at the other focus, with flat reflectors at the ends of the trough. This type of trough reflector produces an uneven light distribution along the painted surface beneath the length of the lamp. Especially there is a lower intensity at the ends of the illuminated painted surface. This is a disadvantage because, for instance, in order to produce the intensity needed at the ends, the intensity at the center of the illuminated painted surface must be higher than necessary.
A second disadvantage arises because the flat ends of the elliptical trough reflectors both trap a significant fraction of the light between the flat ends and scatters the remaining incident light, with only a small fraction contributing to the high intensity area where paint is being stripped.
Furthermore, known elliptical trough reflectors cannot irradiate painted surfaces near walls and corners. Known practical implementations result in a light footprint on the work surface that is well inside the projected footprint of the reflector onto the work surface. In typical applications light from the reflector cannot be used to strip paint from 10% of the surface area.
Impulsive acoustic sources generally are inherently omni-directional. However, in some uses there is a requirement for impulsive sound output to be provided in specific directions. Also, in some cases in which reflectors known-in-the-art are used with impulsive acoustic sources, some emission sources erode during operation so that a source initially at a focus of a reflector erodes away from the focus diminishing its effectiveness. In those cases it would be advantageous to have a reflector which maintained effectiveness even as the source erodes.
It is an object of the present invention: to have reflectors that would reach all the surface area; to have a reflector that both utilizes the light more efficiently and distributes the light more uniformly along work surfaces beneath the lamp.
It is another object of the invention to have end reflectors that both do not trap light and that reflect a large fraction of incident light to the high intensity work surface, for example where paint is being stripped.
It is yet another object of the present invention to have reflectors that redirect impulsive acoustic emission in specific directions.
It is still another object of the present invention to have reflectors that maintain the effectiveness even as electrodes erode.
The present invention addresses foregoing and other objects and provides other advantages by arranging reflector shapes around emissive sources.
The efficacy of light and sound sources depends in part on how the emission from the source is transferred for the intended use. In many applications a reflector is used to direct emitted light or sound onto surfaces or into volumes for processing. The present inventive reflectors can be used to improve the useful output or the efficiency of a source emission. The inventive improvement increases the capability of the source and/or reduces the requirements on the emissive source to accomplish an intended objective.
As discussed before, in general, tubular sources employ reflector troughs with flat end reflectors. In a preferred embodiment of the invention, the flat end reflectors are angled and shaped to direct better the emissions onto the work surface or into the work volume. In applications in which the objective is achieving high intensity on a surface, ellipsoidal end reflectors can both increase the efficiency of transferring light to the surface as well as produce an intensity distribution that is uniform along the axis of the trough. In applications in which the objective is to irradiate a volume, various trough and end shapes may be employed to direct better the emissions, including but not limited to angle flat and parabolic shapes.
In another preferred embodiment of the invention the trough is tapered, so that the top of the reflector is angled with respect to the surface while the foci are maintained. This projects emission outside of the footprint, so that, for instance, an entire surface area can be processed. Another preferred embodiment provides both shaped reflector ends and an angles top of the reflector, taking advantage of both inventive concepts just described.
Also, for some applications, emission is desired that is omni-directional in only one plane (e.g. horizontal), with emission extending above and below that plane up to some angle. Emission is not desired at larger angles and in the other plane (e.g. vertical). One aspect of the invention is to redirect emission into the desired direction. These applications are addressed in yet another preferred embodiment of a reflector that is axi-symmetric or linearsymmetric.
As mentioned above, some emission sources erode during operation. A preferred embodiment provides a reflector trough with shaped ends that maintains the position of the source at the focus as the source erodes.
Accordingly, the invention provides reflective means of efficiently controlling the utilization of light and sound source emission, including angled and shaped end reflectors for troughs, slanted troughs, axi- and linearsymmetric reflectors, and troughs for use with point sources. These shapes include but are not limited to partial ellipsoids, paraboloid, rounded, flat, segmented flat, and hyperbolic and other such geometric shapes and combinations of shapes.
These inventive reflectors are amenable for use in a wide variety of industrial, commercial, military, academic, and environmental applications such as surface treatment (e.g. paint stripping and UV curing), sterilization, geophysical exploration, antibiofouling, lithotripsy, underwater surveillance, sonobuoys, shallow water characterization, mine sweeping, submarine countermeasures, disinfection, destruction of organic compounds, for instance, in industrial waste, groundwater and water supplies, and the like.
It will be appreciated by those skilled in the art that although the following Detailed Description will proceed with reference being made to illustrative embodiments, the drawings, and methods of use, the present invention is not intended to be limited to these embodiments and methods of use. Rather, the present invention is of broad scope is and is intended to be defined as only set forth in the accompanying claims.